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      <div class="doc-title"><a href="folktale.html"><span class="doc-title"><span class="product-name">Folktale</span><span class="version">v2.1.0</span></span></a><ul class="navigation"><li class="navigation-item"><a href="https://github.com/origamitower/folktale" title="">GitHub</a></li><li class="navigation-item"><a href="/docs/support/" title="">Support</a></li><li class="navigation-item"><a href="/docs/v2.1.0/contributing/" title="">Contributing</a></li></ul></div>
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    <div id="content-wrapper"><div id="content-panel"><h1 class="entity-title">identity</h1><div class="highlight-summary"><div><p>The identity combinator; always returns the argument given.</p>
</div></div><div class="definition"><h2 class="section-title" id="signature">Signature</h2><div class="signature">identity(value)</div><div class="type-definition"><div class="type-definition-container"><div class="type-title-container"><strong class="type-title">Type</strong><a class="info" href="/docs/v2.1.0/misc/type-notation/">(what is this?)</a></div><pre class="type"><code class="language-haskell">('a) =&gt; 'a</code></pre></div></div></div><h2 class="section-title">Documentation</h2><div class="documentation"><div><p>The identity combinator; always returns the argument given.</p>
<h2 id="example-">Example:</h2>
<pre><code>const identity = require(&#39;folktale/core/lambda/identity&#39;);

identity(1);
// ==&gt; 1

[1, 2, 3].map(identity);
// ==&gt; [1, 2, 3]
</code></pre><h2 id="why-">Why?</h2>
<p>There aren&#39;t many reasons to use the <code>identity</code> combinator in real
JavaScript code. Readability is the only compelling one. Figuring
out the concept of <code>identity</code> from reading the word <code>identity</code> is
easier than working your way through its implementation.</p>
<p>Compare:</p>
<pre><code>const identity = require(&#39;folktale/core/lambda/identity&#39;);

either.bimap(identity, (counter) =&gt; counter + 1);
</code></pre><p>With:</p>
<pre><code>either.bimap(
  (failure) =&gt; failure,
  (counter) =&gt; counter + 1
)
</code></pre></div></div><div class="members"><h2 class="section-title" id="properties">Properties</h2></div><div class="source-code"><h2 class="section-title" id="source-code">Source Code</h2><div class="source-location">Defined in source/core/lambda/identity.js at line 18, column 0</div><pre class="source-code"><code class="language-javascript">(value) =&gt; value</code></pre></div></div><div id="meta-panel"><div class="meta-section"><div class="meta-field"><strong class="meta-field-title">Stability</strong><div class="meta-field-value">stable</div></div><div class="meta-field"><strong class="meta-field-title">Licence</strong><div class="meta-field-value">MIT</div></div><div class="meta-field"><strong class="meta-field-title">Module</strong><div class="meta-field-value">folktale/core/lambda/identity</div></div></div><div class="table-of-contents"><div class="meta-section-title">On This Page</div><ul class="toc-list level-1"><li class="toc-item"><a href="#signature">Signature</a></li><li class="toc-item"><span class="no-anchor">Documentation</span><ul class="toc-list level-2"><li class="toc-item"><a href="#example-" title="Example:"><div><p>Example:</p>
</div></a></li><li class="toc-item"><a href="#why-" title="Why?"><div><p>Why?</p>
</div></a></li></ul></li><li class="toc-item"><a href="#properties">Properties</a><ul class="toc-list level-2"></ul></li><li class="toc-item"><a href="#source-code">Source Code</a></li></ul></div><div class="meta-section"><strong class="meta-section-title">Authors</strong><div class="meta-field"><strong class="meta-field-title">Copyright</strong><div class="meta-field-value">(c) 2013-2017 Quildreen Motta, and CONTRIBUTORS</div></div><div class="meta-field"><strong class="meta-field-title">Authors</strong><div class="meta-field-value"><ul class="meta-list"><li>Quildreen Motta</li></ul></div></div><div class="meta-field"><strong class="meta-field-title">Maintainers</strong><div class="meta-field-value"><ul class="meta-list"><li>Quildreen Motta &lt;queen@robotlolita.me&gt; (http://robotlolita.me/)</li></ul></div></div></div></div></div>
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